PodSAR: A versatile real-time SAR GMTI surveillance and targeting system

Synthetic aperture radar (SAR) and ground moving target indication (GMTI) systems from an airborne platform are in principle based on very simple concepts. The latter combines radar pulses over a short interval to extract Doppler information in order to detect ground moving targets against a clutter background. The former combines pulses over much longer intervals in a coherent manner to achieve very fine azimuth resolution. However, the many demands that are placed on such systems in terms of resolution, geolocation accuracy and coverage have led to the development of highly sophisticated algorithms. The ability to perform such complex processing in real-time on board the airborne radar platform presents significant computational challenges. This paper describes how a successful implementation of a real-time SAR GMTI system has been achieved with the QinetiQ PodSAR system. It describes the radar system that is mounted on a wide-bodied Andover aircraft. It discusses the design challenges that had to be overcome in order to achieve real-time processing for SAR and GMTI along with showing a number of examples of image exploitation techniques being developed using data from the PodSAR system.